CN109792257A

CN109792257A - High-frequency front-end circuit and communication device

Info

Publication number: CN109792257A
Application number: CN201780059799.3A
Authority: CN
Inventors: 野阪浩司
Original assignee: Murata Manufacturing Co Ltd
Current assignee: Murata Manufacturing Co Ltd
Priority date: 2016-09-27
Filing date: 2017-09-13
Publication date: 2019-05-21
Anticipated expiration: 2037-09-13
Also published as: CN109792257B; US20190214959A1; WO2018061782A1; US10686421B2

Abstract

High-frequency front-end circuit (1) has switching circuit (10), duplexer (20, and capacitor (C) 30), switching circuit (10) includes main switch (SW1), switches over to the connection between public terminal (111) and selection terminal (112)；Auxiliary switch (SW1g), by with main switch (SW1) is mutually exclusive switches on and off, to be switched over to the connection between selection terminal (112) and ground；Main switch (SW2) switches over the connection between public terminal (111) and selection terminal (113)；And auxiliary switch (SW2g), its by with main switch (SW2) is mutually exclusive switches on and off, to be switched over to the connection between selection terminal (113) and ground, wherein, in main switch (SW1, SW2 switch between the second connection type that the first connection type for only having a side to connect in) and both sides connect, capacitor (C) will select terminal (112) to connect with selection terminal (113).

Description

High-frequency front-end circuit and communication device

Technical field

The present invention relates to a kind of high-frequency front-end circuit and communication device with multiple filters.

Background technique

In the past, as support multiband the filter module for having multiple filters, it is known that structure below: have by The switching circuit that multiple filter is selectively connect with antenna terminal (for example, referring to patent document 1).According to the filter Module, such as impedance matching electricity is provided between 1 switching circuit and the multiple filters connected with 1 switching circuit Road.

Existing technical literature

Patent document

Patent document 1: International Publication No. 2013/021626

Summary of the invention

Problems to be solved by the invention

However, needing that impedance matching circuit is respectively arranged to multiple filters, therefore hinder in above-mentioned previous structure Miniaturization.

In addition, when the number of the filter selected by switching circuit is 2 or more, such as using above-mentioned previous structure come into The case where going while sending or receiving CA (the Carrier Aggregation: carrier wave polymerization) of the high-frequency signal of multiple frequency bands etc. When, it is possible to create as follows the problem of.That is, when the number with the filter selected by switching circuit is 1, such as non- It is compared whens the case where CA (non-Carrier Aggregation: non-carrier polymerization) etc., due to the filtering selected by switching circuit The number of device changes and impedance is caused to generate deviation.

Thus, in this case, become difficult by the impedance matching that impedance matching circuit carries out, incurs the increase of loss.

Therefore, the purpose of the present invention is to provide a kind of high-frequency front-end circuit that can be realized miniaturization and low-loss with And communication device.

The solution to the problem

To achieve the goals above, high-frequency front-end circuit involved in one embodiment of the present invention has: switching circuit, The multiple selection terminals being connect with the public terminal being connect with input and output terminal and selectively with the public terminal； First filter is connect with the first choice terminal in the multiple selection terminal；Second filter, with the multiple choosing The second selection terminal connection in terminal is selected, there is the passband different from the passband of the first filter；And first impedance Element, wherein the switching circuit includes the first main switch, by switching on and off, by the public terminal with it is described Be switched between first choice terminal connection and it is disconnected；First auxiliary switch, by connection with first main switch and It disconnects mutually exclusive switched on and off, will be switched to and connect and disconnected between the first choice terminal and ground；Second is main Switch, by not switched on and off switching on and off of being restricted by first main switch, by the public terminal It is switched to and connect and disconnected between the second selection terminal；And second auxiliary switch, by being opened with second master Pass is mutually exclusive to be switched on and off, and will be switched to connection and disconnected, the switch between the second selection terminal and ground The first connection type and first master that circuit only has a side to connect in first main switch and second main switch Switch and this two side of second main switch connect the second connection type between switch, first impedor be connected to by The first choice terminal selects terminal and institute with the node on the path of first filter connection and by described second State the node on the path of second filter connection.

It is as a result, the first connection type that an only side connects in the first main switch and the second main switch in switching circuit When, the first impedor is connected to ground via the side in the first auxiliary switch and the second auxiliary switch.Therefore, the first impedance at this time Element works as the impedor of impedance matching circuit.It on the other hand, is the first main switch and described in switching circuit When the second connection type that this two side of the second main switch connects, the both ends of the first impedor are main via the first main switch and second Switch is short-circuited.Therefore, the first impedor does not work at this time.That is, becoming impedance without additional according to the method The impedor of match circuit can change impedance matching circuit according to the connection type of switching circuit, therefore can be realized Miniaturization and low-loss.

Alternatively, it is also possible to be, the switching circuit only has a side in first main switch and second main switch The second connection type that the first connection type connected and first main switch and this two side of second main switch connect it Between switch, only the switching circuit be first connection type and second connection type in first connection side When formula, first impedor makes the impedance and benchmark impedance matching of the input and output terminal.

By switched like this according to the first connection type and the second connection type whether by the first impedor into Row matching, is equal to using 1 impedor (the first impedor) and constitutes 2 impedance matching circuits.Therefore, it can cut down The parts number of impedance matching circuit is constituted, therefore can be realized miniaturization.

Alternatively, it is also possible to be, the high-frequency front-end circuit is also equipped with the second impedance for being connected to ground the public terminal Element is first company that first main switch is connected with an only side in second main switch in the switching circuit When connecing mode, first impedor makes the impedance of the input and output terminal with the parallel circuit of second impedor With benchmark impedance matching, in the institute that the switching circuit is connected for first main switch with second main switch this two side When stating the second connection type, only have second impedor to make institute in first impedor and second impedor State the impedance and the benchmark impedance matching of input and output terminal.

It, can be by being hindered by the first impedor with second as a result, in the case where switching circuit is the first connection type The impedance matching circuit that the parallel circuit of anti-element is constituted makes the impedance and benchmark impedance matching of input and output terminal, is opening In the case that powered-down road is the second connection type, it can make to input by the impedance matching circuit being made of the second impedor The impedance and benchmark impedance matching of output terminal.Therefore, no matter switching circuit is the first connection type or the second connection side Formula can realize low-loss.

Alternatively, it is also possible to be, the first filter and the second filter are that have the elasticity of elastic wave resonator Wave filter.

Thereby, it is possible to (the high selection degree) filter characteristic for obtaining having steepness excellent, small-sized and low clearance One filter and second filter.That is, according to the method, can be realized while realizing further miniaturization, The high-frequency front-end circuit of low-loss and high selection degree.

Alternatively, it is also possible to be, first impedor is capacitor, and second impedor is inductor.

Here, constructively, electricity is presented in the impedance for constituting the acoustic wave filter of first filter and second filter The case where capacitive, is more.Therefore, by the way that capacitor is used as the first impedor, inductor is used as to the second impedor no matter Switching circuit is the first connection type or the second connection type, can make the impedance and benchmark impedance of input and output terminal Matching, therefore can be realized low-loss.That is, can be realized while realizing miniaturization, low damage according to the method The high-frequency front-end circuit of consumption and high selection degree.

Alternatively, it is also possible to be, in the passband of single first filter when in terms of the first choice terminals side Susceptance ingredient in the passband of single second filter when susceptance ingredient is less than in terms of the second selection terminals side, institute It states high-frequency front-end circuit and is also equipped with the third impedor for being connected to ground the first choice terminal, be in the switching circuit When first connection type that only described first main switch is connected, first impedor is the same as second impedor The impedance and the benchmark impedance matching for making the input and output terminal with the parallel circuit of the third impedor, in institute When stating first connection type that switching circuit is the only described second main switch connection, first impedor is the same as described The parallel circuit of second impedor makes the impedance and the benchmark impedance matching of the input and output terminal, in the switch When circuit is second connection type, second impedor makes described defeated with the parallel circuit of the third impedor Enter the impedance and the benchmark impedance matching of output terminal.

Even susceptance ingredient in the passband of single first filter when as a result, in terms of first choice terminal be less than from It the case where susceptance ingredient in the passband of single second filter of second selection terminal when seeing, also can be according to switching circuit Connection type changes impedance matching circuit, therefore can be realized miniaturization and low-loss.

Alternatively, it is also possible to be, the third impedor is capacitor, is the feelings of capacitor in first impedor Under condition, the capacitance of the third impedor is smaller than the capacitance of first impedor.

The above-mentioned susceptance ingredient in single first filter and the respective passband of single second filter is greater than j0 as a result, When, that is, when capacitive character is presented in single first filter and single second filter respectively in passband, can be realized miniaturization and Low-loss.

Alternatively, it is also possible to be, in the passband of single first filter when in terms of the first choice terminals side Susceptance ingredient in the passband of single second filter when susceptance ingredient is less than in terms of the second selection terminals side, institute The breaking capacitance for stating the first auxiliary switch is bigger than the breaking capacitance of second auxiliary switch.

Thereby, it is possible to cut down the number of impedor, therefore it can be realized further miniaturization.

Alternatively, it is also possible to be, in the passband of single first filter when in terms of the first choice terminals side Susceptance ingredient in the passband of single second filter when susceptance ingredient is in terms of the second selection terminals side is same.

When no matter switching circuit is the first connection type of only the first main switch connection as a result, or only second is main When the first connection type of switch connection, the admittance at input and output terminal can be made to move by additional first impedor Position to the roughly the same position on dmittance chart.Therefore, by the constant of the first impedor of appropriate adjustment, either it is above-mentioned which Kind situation can make the impedance and benchmark impedance matching of input and output terminal.Therefore, it is able to suppress the increase of number of components, Therefore it can be realized further miniaturization.

Alternatively, it is also possible to be, at least one party in the first filter and the second filter is by multiple filters It constitutes, the multiple filter is the multiplexer connecting after a respective terminal is connected jointly with the switching circuit.

It for example can be realized the high-frequency front-end circuit for supporting the transmitting and receiving of CA as a result,.

Alternatively, it is also possible to be, the switching circuit only has a side in first main switch and second main switch The second connection type that the first connection type connected and first main switch and this two side of second main switch connect it Between switch, the high-frequency front-end circuit is also equipped with control unit, and the control unit is carrying out carrier wave polymerization, sending or receiving simultaneously First band to the passband distribution of the first filter and the second band of the passband distribution to the second filter When, make the switching circuit second connection type, is carrying out non-carrier polymerization, sending or receiving the first band When with either in the second band, make the switching circuit first connection type.

In addition, high-frequency front-end circuit involved in another mode of the invention has: switching circuit has and input The public terminal of output terminal connection and the multiple selection terminals selectively being connect with the public terminal；First filtering Device is connect with the first choice terminal in the multiple selection terminal；In second filter, with the multiple selection terminal Second selection terminal connection；And first impedor, wherein the switching circuit includes first switch, by described One selection terminal is selectively connect with the one party in the public terminal and ground terminal；And second switch, it will be described Second selection terminal is selectively connect with the one party in the public terminal and ground terminal, the first impedor connection Terminal is selected in the node on the path for linking the first choice terminal and the first filter and by described second With the node on the path of second filter connection.

Thereby, it is possible to reduce the quantity of switch, therefore it can be realized miniaturization.

Alternatively, it is also possible to be, the high-frequency front-end circuit has multiple groups, and each group has the as the switching circuit One switching circuit, the first filter, the second filter and first impedor, the high-frequency front-end circuit It is also equipped with: second switch circuit, with public terminal, first choice terminal and the second selection terminal；And the 4th impedance Element, wherein the first choice terminal possessed by the second switch circuit selectively with the second switch circuit institute One party in the public terminal and ground terminal having connects, second selection possessed by the second switch circuit Terminal is selectively connect with the public terminal possessed by the second switch circuit and the one party in ground terminal, described more The public terminal possessed by the first switch circuit in a group in a group is had with the second switch circuit The first choice terminal having connects, institute possessed by the first switch circuit in another group in the multiple group It states public terminal to connect with the second selection terminal possessed by the second switch circuit, the 4th impedor connection In by the first choice terminal possessed by the second switch circuit with one group in the first switch circuit Node on the path of possessed public terminal connection and will be described second possessed by the second switch circuit It selects on the path of the public terminal connection possessed by the first switch circuit in terminal and another described group Node.

Thereby, it is possible to 4 or more frequency bands are supported while realizing miniaturization and low-loss.

In addition, communication device involved in one embodiment of the present invention has: RF signal processing circuit, to utilize antenna The high-frequency signal that element transmits and receives is handled；And any of the above-described a high-frequency front-end circuit, the antenna element with The high-frequency signal is transmitted between the RF signal processing circuit.

Thereby, it is possible to provide the communication device that can be realized miniaturization and low-loss.

The effect of invention

Related high-frequency front-end circuit and communication device according to the present invention can be realized miniaturization and low-loss.

Detailed description of the invention

Fig. 1 is the structure chart of high-frequency front-end circuit involved in embodiment 1.

Fig. 2A is an example for indicating the block diagram of the switching circuit in embodiment 1.

Fig. 2 B is another example for indicating the block diagram of the switching circuit in embodiment 1.

Fig. 3 A be schematically show selection multiple equipment when embodiment 1 involved in high-frequency front-end circuit structure Figure.

Fig. 3 B is the equivalent circuit diagram of Fig. 3 A.

Fig. 4 A is the knot of high-frequency front-end circuit involved in the embodiment 1 that schematically shows when selecting single equipment The figure of structure.

Fig. 4 B is the equivalent circuit diagram of Fig. 4 A.

Fig. 5 is the Smith chart for illustrating the impedance matching in embodiment 1.

Fig. 6 A is to indicate to select impedance matching circuit when multiple equipment to keep the history of the variation of impedance generation close in embodiment 1 This circle diagram.

Fig. 6 B is to indicate to select impedance matching circuit when single equipment to keep the history of the variation of impedance generation close in embodiment 1 This circle diagram.

Fig. 7 is the figure for indicating to support the characteristic of the single duplexer of Band26 in embodiment.

Fig. 8 is the figure for indicating to support the characteristic of the single duplexer of Band12 in embodiment.

Fig. 9 A is the first figure for indicating the characteristic in the state of bundling 2 duplexers in embodiment.

Fig. 9 B is the second figure for indicating the characteristic in the state of bundling 2 duplexers in embodiment.

Figure 10 A is characteristic when indicating the CA of Band26 and Band12 in the high-frequency front-end circuit involved in embodiment First figure.

Figure 10 B is characteristic when indicating the CA of Band26 and Band12 in the high-frequency front-end circuit involved in embodiment Second figure.

Figure 11 A is the figure of characteristic when indicating the non-CA of Band26 in the high-frequency front-end circuit involved in embodiment.

Figure 11 B is the figure of characteristic when indicating the non-CA of Band12 in the high-frequency front-end circuit involved in embodiment.

Figure 12 is the structure chart of high-frequency front-end circuit involved in the variation 1 of embodiment 1.

Figure 13 A is high frequency front-end involved in the variation 1 of the embodiment 1 when schematically showing selection multiple equipment The figure of the structure of circuit.

Figure 13 B is the equivalent circuit diagram of Figure 13 A.

Figure 14 A is to schematically show the deformation for selecting filter as the embodiment 1 in the case where single equipment The figure of the structure of high-frequency front-end circuit involved in example 1.

Figure 14 B is the equivalent circuit diagram of Figure 14 A.

Figure 15 A is to schematically show the deformation for selecting duplexer as the embodiment 1 in the case where single equipment The figure of the structure of high-frequency front-end circuit involved in example 1.

Figure 15 B is the equivalent circuit diagram of Figure 15 A.

Figure 16 is the Smith chart for illustrating the impedance matching in the variation 1 of embodiment 1.

Figure 17 is the structure chart of high-frequency front-end circuit involved in the variation 2 of embodiment 1.

Figure 18 is the structure chart of high-frequency front-end circuit involved in embodiment 2.

Figure 19 is the structure chart of high-frequency front-end circuit involved in embodiment 3 and its peripheral circuit.

Figure 20 is the structure chart of the first case of high-frequency front-end circuit involved in other embodiment.

Figure 21 is the structure chart of the second case of high-frequency front-end circuit involved in other embodiment.

Specific embodiment

In the following, carrying out the embodiment that the present invention will be described in detail using embodiment and attached drawing.In addition, embodiment party described below Formula indicates master or concrete example.Numerical value shown in following embodiment, shape, material, structural element, structure The configuration of element and connection type etc. are an examples, and purport does not simultaneously lie in the restriction present invention.By following embodiment In structural element in the structural element for not being recorded in independent claims be illustrated as arbitrary structural element.Separately Outside, in the various figures, identical label is marked to substantially the same structure, repeat description is omitted or simplified sometimes.

(embodiment 1)

[1. summary]

[1-1. structure]

Fig. 1 is the structure chart of high-frequency front-end circuit 1 involved in embodiment 1.

High-frequency front-end circuit 1 is in antenna element (not shown), amplifier (not shown) and RFIC (Radio Frequency IntegratedCircuit: RF IC, not shown) between transmit the circuit of high-frequency signal.These days Thread elements, amplifier and RFIC are set to the outside of high-frequency front-end circuit 1.Therefore, in the present embodiment, high frequency front-end electricity Realize the function as multiplexer in road 1.In addition, amplifier can also be built in high-frequency front-end circuit 1.

In the present embodiment, high-frequency front-end circuit 1 supports LTE (Long Term Evolution: long term evolution), passes Pass the Band specified in 3GPP (Third Generation Partnership Project: third generation partner program) The high-frequency signal of (frequency range).Specifically, high-frequency front-end circuit 1 supports defined Band26 and Band12 in 3 gpp, transmitting The high-frequency signal of the Band.

In addition, in the following, " Band as defined in 3 gpp " is only called " Band " sometimes, by the reception band (Rx of each Band Band) or send band (Tx band) and simplifiedly indicates that the word for receiving band or transmission band is called with frequency range name and its end is additional, Such as the reception band for Band26, the address as " B26Rx ".

In the present embodiment, high-frequency front-end circuit 1 is input to antenna (ANT) terminal after receiving using antenna element 101 high-frequency signal (being herein high-frequency received signal) is filtered to after passing through the high-frequency signal of assigned frequency, from more A independent terminals (be herein 2 receiving terminal, specifically, the B26Rx terminal 102Rx of the receiving terminal as Band26 with And the B12Rx terminal 103Rx of the receiving terminal as Band12) via amplifier it is output to RFIC.Alternatively, opposite to thatly, It (is herein 2 transmission terminals, specifically, as Band26 that high-frequency front-end circuit 1 will be input to multiple independent terminals from RFIC Transmission terminal B26Tx terminal 102Tx and the receiving terminal as Band12 B12Tx terminal 103Tx) high-frequency signal (sending signal herein for high frequency) amplifies, and is filtered after passing through the high-frequency signal of assigned frequency later from ANT Terminal 101 is output to antenna element.In the present embodiment, ANT terminal 101 is the input and output for outputting and inputting high-frequency signal Terminal.In addition, input and output terminal is not limited to connect with antenna element, can also be connect with other circuit elements such as amplifier. That is, the ANT terminal 101 in present embodiment is also possible to the terminal with connections such as amplifiers.

Specifically, high-frequency front-end circuit 1 has switching circuit 10, multiple filters (in the present embodiment, for by sending out It the duplexer 20 that send filter 21 and receiving filter 22 to constitute and is made of transmitting filter 31 and receiving filter 32 Duplexer 30) and capacitor C (the first impedor).In addition, in the present embodiment, high-frequency front-end circuit 1 is also equipped with electricity Sensor L (the second impedor).

Multiple selection terminals that switching circuit 10 has public terminal 111 and selectively connect with public terminal 111 (being in the present embodiment, 2 selection terminals 112 (first choice terminal) and selection terminal 113 (the second selection terminal)).? This, public terminal 111 is connect with the ANT terminal 101 of high-frequency front-end circuit 1, and multiple selection terminals are via above-mentioned multiple filters To be independently connected with multiple independent terminals of high-frequency front-end circuit 1.

Specifically, switching circuit 10 has the master of SPST (Single-Pole, Single-Throw: single-pole single-throw(SPST) type Switch SW1 (the first main switch), main switch SW1 by connect (conducting) and disconnection (non-conduction) by public terminal 111 and Connection (conducting) and disconnected (non-conduction) is switched between selection terminal 112 (first choice terminal).In addition, switching circuit 10 Auxiliary switch SW1g (the first auxiliary switch) with SPST type, auxiliary switch SW1g by with main switch SW1 (the first main switch) phase Exclusive switches on and off, and terminal 112 (first choice terminal) will be selected to connect and disconnected with being switched between ground.Separately Outside, there is switching circuit 10 the main switch SW2 (the second main switch) of SPST type, main switch SW2 to pass through not main switch SW1's Switching on and off of being restricted is switched on and off, will be cut between public terminal 111 and selection terminal 113 (the second selection terminal) Be changed to connection and it is disconnected.In addition, switching circuit 10 has the auxiliary switch SW2g (the second auxiliary switch) of SPST type, the auxiliary switch SW2g by with main switch SW2 (the second main switch) is mutually exclusive switches on and off, (the second selection end of terminal 113 will be selected Son) it connect and disconnected with being switched between ground.

Here, " exclusive switches on and off " refers to: in the case where a side connects, another party is disconnected, and is disconnected in a side In the case of another party connect.Therefore, between main switch SW1 and auxiliary switch SW1g, in the case where main switch SW1 is connected, pair is opened It closes SW1g to disconnect, in the case where main switch SW1 is disconnected, auxiliary switch SW1g is connected.In addition, in main switch SW2 and auxiliary switch SW2g Between, in the case where main switch SW2 is connected, auxiliary switch SW2g is disconnected, the auxiliary switch SW2g in the case where main switch SW2 is disconnected It connects.

In addition, the switching on and off for not main switch SW1 that switch on and off of main switch SW2 made about refers to: being opened with master Switching on and off for pass SW1 is unrelated, and main switch SW2 can both can turn on and may also disconnect.That is, main switch SW1 is opened with master SW2 is closed to switch on and off independently of one another.

According to the switching circuit 10 constituted in this way, the main switch SW1 between public terminal 111 and selection terminal 112 is connect When logical, the auxiliary switch SW1g between terminal 112 and ground terminal is selected to disconnect, thus, it is possible to by public terminal 111 and selection terminal It is connected between 112.On the other hand, when the main switch SW1 between public terminal 111 and selection terminal 112 is disconnected, terminal is selected Auxiliary switch SW1g between 112 and ground terminal is connected, and thus becomes disconnected between public terminal 111 and selection terminal 112, and And it can will be isolated between public terminal 111 and selection terminal 112.These items are not limited to the master connecting with selection terminal 112 Switch SW1 and auxiliary switch SW1g is also same about the main switch SW2 and auxiliary switch SW2g connecting with selection terminal 113.

As each switch (main switch SW1 and SW2, auxiliary switch SW1g and SW2g) for constituting this switching circuit 10, such as Can enumerate diode switch or by GaAs or CMOS (Complementary Metal Oxide Semiconductor: Complementary metal oxide semiconductor) constitute FET (Field Effect Transistor: field effect transistor) switch.Separately Outside, switching circuit 10 is also configured to the switch IC (Integrated Circuit: integrated circuit) with multiple switch.Separately Outside, each switch is not limitedly formed the semiconductor switch of semiconductor substrate, is also possible to by MEMS (Micro Electro Mechanical Systems: microelectromechanical systems) constitute mechanical switch.

In addition, the switching circuit 10 used in the high-frequency circuits such as high-frequency front-end circuit 1 can be generally expressed as such as Fig. 2A With block diagram shown in Fig. 2 B.Fig. 2A is an example for indicating the block diagram of the switching circuit 10 in present embodiment.Fig. 2 B is the block diagram Another example.Even the switching circuit 10 of the SPDT as shown in these block diagrams (single-pole double throw) type, for internal structure, Have 2 main switch SW1 shown in FIG. 1 and SW2 and 2 auxiliary switch SW1g and SW2g.That is, being not limited in switch electricity Have the structure of 2 main switch SW1 and SW2 and 2 auxiliary switch SW1g and SW2g with being explicitly illustrated in road 10, also includes as schemed The knot of 2 main switch SW1 and a part in SW2 and 2 auxiliary switch SW1g and SW2g is omitted shown in 2A and Fig. 2 B like that Structure.

Specifically, switching circuit 10 shown in Fig. 2A is that main switch SW1 and main switch SW2 connect on and off independently of one another The structure opened.That is, switching circuit 10 shown in the figure can be realized any of following connection type: main switch Only have a side to connect in SW1 and SW2；This two side of main switch SW1 and SW2 connects；And this two side of main switch SW1 and SW2 disconnects.

Switching circuit 10 shown in Fig. 2 B be represented as in most cases public terminal 111 and 2 selection terminal 112 and There was only the structure of side connection in 113.In other words, switching circuit 10 shown in the figure is represented as following knot in most cases Structure: although can be realized in main switch SW1 and SW2 only have a side connect connection type, can not achieve main switch SW1 and The connection type that the connection type and this two side of main switch SW1 and SW2 that this two side of SW2 connects disconnect.But even figure Shown in switching circuit 10, as long as actual structure have 2 main switch SW1 and SW2 and 2 auxiliary switch SW1g and SW2g, it will be able to realize connection type identical with switching circuit 10 shown in Fig. 1 or Fig. 2A.Therefore, in present embodiment Not shown in block diagram etc., simply statement limits switching circuit 10, but is limited by internal circuit structure or connection type It is fixed.

In the present embodiment, duplexer 20 supports Band26, is made of transmitting filter 21 and receiving filter 22, should Transmitting filter 21 includes the Tx band of Band26 in the pass-band, and includes the Rx band of Band26 in attenuation band, this accepts filter Device 22 includes the Rx band of Band26 in the pass-band, and includes the Tx band of Band26 in attenuation band.The one of the transmitting filter 21 One input and output terminal of a input and output terminal (being herein output terminal) and the receiving filter 22 (is herein input terminal Son) (binding) is connected jointly after the public terminal of duplexer 20, it is connect with the selection terminal 112 of switching circuit 10.In addition, hair Another input and output terminal (being herein input terminal) of filter 21 is sent to connect with B26Tx terminal 102Tx.In addition, receiving Another input and output terminal (being herein output terminal) of filter 22 is connect with B26Rx terminal 102Rx.

Duplexer 30 has the passband different from duplexer 20, and duplexer 30 supports Band12 in the present embodiment.It should Duplexer 30 is made of transmitting filter 31 and receiving filter 32, which includes the Tx of Band12 in the pass-band Band, and including the Rx band of Band12 in attenuation band, which includes the Rx band of Band12 in the pass-band, and is declining Subtract the Tx band in band including Band12.An input and output terminal (being herein output terminal) for the transmitting filter 31 and this connect The input and output terminal (being herein input terminal) for receiving filter 32 connects (binding) in the common end of duplexer 30 jointly After son, it is connect with the selection terminal 113 of switching circuit 10.In addition, another input and output terminal of transmitting filter 31 is (herein For input terminal) it is connect with B12Tx terminal 103Tx.In addition, receiving filter 32 another input and output terminal (herein for Output terminal) it is connect with B12Rx terminal 103Rx.

In the present embodiment, these duplexers 20 and 30 (first filter and second filters) are humorous with elastic wave The acoustic wave filter of vibration device.Specifically, constitute duplexer 20 transmitting filter 21 and receiving filter 22 be respectively by The acoustic wave filter that circuit including elastic wave resonator is constituted, also, constitute the transmitting filter 31 of duplexer 30 and connect Receiving filter 32 is the acoustic wave filter being made of the circuit including elastic wave resonator respectively.Elastic wave resonator for example by It is constituted using the resonator of surface acoustic wave, bulk wave or boundary acoustic wave.

In addition, the passband of duplexer 20 and the passband of duplexer 30 are different, frequency is not overlapped.I.e. it is capable to 2 or more the filters (transmission in the present embodiment, including composition duplexer 20 connected jointly by switching circuit 10 Filter 21 and receiving filter 22 and this 4 filtering of transmitting filter 31 and receiving filter 32 for constituting duplexer 30 Device) passband frequency it is different, be not overlapped.

Capacitor C will select terminal 112 (first choice terminal) to connect with selection terminal 113 (the second selection terminal) First impedor.Here, capacitor C " connecting selection terminal 112 with selection terminal 113 " is not limited to the following structures: capacitor One end of device C is directly connected to selection terminal 112, and the other end and the selection terminal 113 of capacitor C is directly connected to.For example, capacitor Device C can also be connected to the transmission line that terminal 112 and duplexer 20 will be selected to link with one end, and the other end, which is connected to, will select end The transmission line that son 113 links with duplexer 30.Selection terminal 112 is connected with duplexer 20 that is, capacitor C is connected to Node on the path of knot and by the node on the path for selecting terminal 113 and duplexer 30 to link.

Inductor L is the second impedor for being connected to ground public terminal 111.Here, inductor L is " by public terminal 111 are connected to ground " it is not limited to the following structures: one end of inductor L is directly connected to public terminal 111, the other end of capacitor C It is directly connected to ground.For example, inductor L can also be connected to the transmission for linking ANT terminal 101 and public terminal 111 with one end Route.

The structure of high-frequency front-end circuit 1 is explained above, but the structure of the high-frequency front-end circuit 1 is without being limited thereto.For example, The Band that high-frequency front-end circuit 1 is supported is not limited to Band26 and Band12, is also possible to other Band, the Band's supported Quantity is also not necessarily limited to 2, is also possible to 3 or more.Therefore, the selection number of terminal of switching circuit 10, duplexer (or filtering Device) number and the number etc. of independent terminals of high-frequency front-end circuit 1 be not limited to above-mentioned number.That is, switch electricity Road 10 also can have n (integer that n is 3 or more) main switches and n auxiliary switch.

[1-2. movement]

The high-frequency front-end circuit 1 constituted as described above according to the control signal from the control units (not shown) such as RFIC, It acts as follows.

That is, switching circuit 10 only has a side in main switch SW1 (the first main switch) and main switch SW2 (the second main switch) Switch between the second connection type that the first connection type connected and this two side of main switch SW1 and SW2 connect.

Specifically, switching circuit 10 sends or receives when carrying out CA, simultaneously to duplexer 20 (first filter) Passband distribution Band26 (first band) and Band12 (second to the distribution of the passband of duplexer 30 (second filter) Frequency band) when, become the second above-mentioned connection type.That is, in CA, in switching circuit 10 main switch SW1 and SW2 this Two sides connect, and thus select multiple equipment (being herein 2 equipment i.e. duplexer 20 and 30, hereinafter referred to as " more equipment ").It is tied Fruit, selected by high-frequency signal that high-frequency front-end circuit 1 will be transmitted between antenna element (not shown) and RFIC (not shown) utilizes 2 duplexers 20 and 30 selected transmit after being filtered.

On the other hand, switching circuit 10 when carrying out non-CA, send or receive any in Band26 and Band12 Fang Shi becomes the first above-mentioned connection type.That is, in non-CA, in switching circuit 10, main switch SW1 and SW2 In only a side connect, thus select single equipment (be herein the side in duplexer 20 and 30, it is hereinafter referred to as " single to set It is standby ").As a result, the high-frequency signal that high-frequency front-end circuit 1 will be transmitted between antenna element (not shown) and RFIC (not shown) It is transmitted after being filtered using selected 1 duplexer 20 or 30.

Fig. 3 A is 1 institute of embodiment schematically shown when selecting multiple equipment (being herein 2 duplexers 20 and 30) The figure of the structure for the high-frequency front-end circuit 1 being related to.Fig. 3 B is the equivalent circuit diagram of Fig. 3 A.In addition, in figure 3 a, it is indicated by the solid line The inoperative part on circuit is represented by dashed line in the part worked on circuit.This is in later identical figure It is same.In addition, for the sake of simplicity, below to be inserted into the inductance between the terminal as the switch connected in switching circuit 10 Device and resistance are zero to be illustrated.Therefore, in actual circuit design, capacitor C (the first impedor) and inductor L The constant of (the second impedor) etc. is sometimes different from value described below.

As shown in these figures, in the case where selecting 2 duplexers 20 and 30, the both ends of capacitor C are via 2 main switches SW1 and SW2 are short-circuited.Therefore, in this case, capacitor C does not work, selected 2 duplexers 20 and 30 it is public Terminal (terminal of 101 side of ANT terminal) with only connect by inductor L (the second impedor) between ground.That is, When switching circuit 10 is the second connection type (that is, this two side of main switch SW1 and SW2 connects), pass through capacitor C (the first impedance Element) and inductor L (the second impedor) in only inductor L make ANT terminal 101 impedance and benchmark impedance matching. In other words, at this point, impedance matching circuit is made of inductor L.

Fig. 4 A is involved in the embodiment 1 that schematically shows when selecting single equipment (being herein duplexer 20) The figure of the structure of high-frequency front-end circuit 1.Fig. 4 B is the equivalent circuit diagram of Fig. 4 A.

Here, in the present embodiment, about connection type when selecting single equipment, in the feelings of selection duplexer 20 In the case where condition and selection duplexer 30, in addition to the main switch SW1 and SW2 and auxiliary switch SW1g and SW2g tune switched on and off Other than changing, other is same.Therefore, the case where illustrating the case where selecting duplexer 20 below, omitting selection duplexer 30 Explanation.

As shown in these figures, only select 1 duplexer 20 in the case where, capacitor C via with non-selected duplexer 30 corresponding auxiliary switch SW2g are connected to ground (shunt ground connection).Therefore, in this case, the public affairs of selected duplexer 20 Connected altogether by capacitor C (the first impedor) with the parallel circuit of inductor L (the second impedor) between terminal and ground It connects.That is, leading to when switching circuit 10 is the first connection type (that is, only having a side to connect in main switch SW1 and SW2) Crossing capacitor C (the first impedor) makes the impedance of ANT terminal 101 with the parallel circuit of inductor L (the second impedor) With benchmark impedance matching.In other words, at this point, impedance matching circuit is made of the parallel circuit of capacitor C and inductor L.

In this way, according to the present embodiment, it, can be more for selecting without the additional impedor for becoming impedance matching circuit The case where the case where equipment and only selection single equipment, changes impedance matching (impedance matching circuit).That is, selecting In the case where more equipment, make only have inductor L to make in capacitor C (the first impedor) and inductor L (the second impedor) It works for impedance matching circuit, in the case where selecting multiple equipment, makes capacitor C (the first impedor) and inductor L (the second impedor) this two side is worked as impedance matching circuit.

[1-3. impedance matching]

In the following, illustrating the principle of the impedance matching in present embodiment.

Fig. 5 is the Smith chart for illustrating the impedance matching in present embodiment.In addition, sometimes close using history below This circle diagram illustrates the admittance reciprocal as impedance.Therefore, the imaginary number components of admittance, that is, susceptance ingredient is carried out sometimes below Illustrate, alternatively, using should not be expressed in Smith chart originally and should be expressed in dmittance chart etc. conductances circle etc. expression come into Row explanation.In addition, impedance and admittance when explanation is in terms of 101 side of ANT terminal below.That is, by being connect from terminal 112 is selected The susceptance ingredient of single duplexer 20 when the terminal of side is seen as single duplexer 20 susceptance ingredient or from selection end The susceptance ingredient of single duplexer 20 when sub 112 sides are seen is illustrated.Similarly, it will be connect from terminal 113 is selected The susceptance ingredient of single duplexer 30 when the terminal of side is seen as single duplexer 30 susceptance ingredient or from selection end The susceptance ingredient of single duplexer 20 when sub 113 sides are seen is illustrated.

Constructively, capacitive character is presented in the duplexer 20 being made of acoustic wave filter and 30 respective impedances.Specifically Say that the impedance (hereinafter referred to as " DPX monomer properties ") of single duplexer 20 and single duplexer 30 is designed to the history in Fig. 5 in ground The rectangle part of " DPX monomer properties " is expressed as on this close circle diagram.

Therefore, the public terminal of this 2 duplexers 20 and 30 is connected to the impedance obtained after (binding) jointly (hereinafter referred to as " DPX bundlees characteristic ") it is located at the circular portion that " DPX bundlees characteristic " is expressed as on the Smith chart of Fig. 5.Specifically, In itself the respective passband of the duplexer 20 being made of acoustic wave filter and 30 (from frequency band), the other side side bundled is duplexing Device works as capacitor.That is, a duplexer in duplexer 20 and 30 to become another from frequency band double The attenuation band of work device.Therefore, DPX bundlees characteristic and capacitive character is further presented compared to DPX monomer properties, ideally, is located at Position after deasil being shifted on Smith chart along equal susceptance circle.

In general, in order to make these DPX monomer properties impedance and DPX binding characteristic impedance and benchmark impedance (such as 50 Ω) matching, will be arranged the inductor for being connected to ground the public terminal of duplexer as impedance matching circuit.But It is that DPX monomer properties and DPX binding characteristic generate deviation on Smith chart, it is therefore desirable to enable the inductance value of inductor The case where the case where enough 1 duplexers for selection and 2 duplexers of selection, is changed.

Have multiple inductors of mutually different inductance value as impedance matching electricity thus, for example contemplating setting Road, the structure for switching multiple inductor by switching, if but this impedance matching circuit be then difficult to minimize.

It in contrast, in the present embodiment, can be for choosing without the additional impedor for becoming impedance matching circuit The case where 2 duplexers of the case where selecting 1 duplexer and selection, changes impedance matching (impedance matching circuit), therefore can be real Now minimize.

Specifically, the inductance value of inductor L is configured to obtain impedance matching when selecting 2 duplexers 20 and 30 (that is, with benchmark impedance matching).

For example, when the inductance value of inductor L is set as L, at frequency f, due in public terminal (101 side of ANT terminal Terminal) and ground between shift amount (variable quantity) the i.e. L of susceptance caused by added inductor L shift | Δ B_L| it is expressed as | Δ B_L |=|-j (1/ (2 π fL)) |.That is, impedance widdershins shifts L on Smith chart when adding inductor L Displacement | Δ B_L| amount.Thus, when the susceptance (imaginary number components of admittance) that DPX is bundled characteristic is set as B₁When, by inductor L sets the inductance value L for meeting following formula, can obtain impedance matching when selecting 2 duplexers 20 and 30.

B₁=|-j (1/ (2 π fL))) |

On the other hand, when only selecting 1 duplexer 20 or 30, the displacement of the L due to caused by inductor L | Δ B_L|, Impedance is shifted compared to benchmark impedance to inductive.But when only selecting 1 duplexer 20 or 30, capacitor C is acted as With, therefore the capacitance (capacitance value) by suitably setting capacitor C, impedance matching can be obtained.

Specifically, when the capacitance of capacitor C is set as C, at frequency f, due to the additional capacitor for being diverted to ground The shift amount of susceptance caused by device C, that is, C displacement | Δ B_C| it is expressed as | Δ B_C|=| j2 π fC |.That is, when adding the electricity When container C, impedance deasil shifts C displacement on Smith chart | Δ B_C| amount.Thus, when by DPX monomer properties Susceptance is set as B₂When, it, can be when only selecting 1 duplexer 20 or 30 by meeting the capacitance C of following formula to capacitor C setting Obtain impedance matching.

B₂+ | j2 π fC |=|-j (1/ (2 π fL)) |

In this way, according to the present embodiment, without the additional impedor for becoming impedance matching circuit, matching 2 can be constituted The impedance matching circuit of a impedance state (DPX bundlees characteristic and DPX monomer properties).

In other words, impedance matching circuit with this configuration, resistance when seeing duplexer 20 and 30 side from ANT terminal 101 It is anti-to change as follows.

Fig. 6 A indicates to select when more equipment (2 duplexers 20 of selection and 30 when) impedance matching circuit to make impedance The Smith chart of variation.Fig. 6 B is impedance matching (when selecting the side in duplexer 20 and 30) when indicating selection single equipment The Smith chart for the variation that impedance occurs for circuit.

As shown in Figure 6A, in the case where selecting 2 duplexers 20 and 30, the impedance of DPX binding characteristic is configured impedance The inductor L displacement L displacement of match circuit | Δ B_L| amount, thus with benchmark impedance matching.Therefore, 2 duplexs are being selected In the case where device 20 and 30, loss caused by high-frequency front-end circuit 1 is able to suppress because of impedance mismatch, therefore can be realized low damage Consumptionization.

On the other hand, as shown in Figure 6B, in the case where selecting 1 duplexer 20 or 30, the impedance quilt of DPX monomer properties Constitute the capacitor C displacement C displacement of impedance matching circuit | Δ B_C| amount, thus displacement for DPX bundle characteristic it is roughly the same Impedance.That is, impedance (DPX bundlees characteristic) and selection 1 when capacitor C has to 2 duplexers 20 of selection and 30 The capacitance that the impedance deviation between impedance (DPX monomer properties) when a duplexer 20 or 30 compensates.Then, C is shifted Displacement | Δ B_C| amount after DPX monomer properties impedance be configured impedance matching circuit inductor L displacement L displacement | Δ B_L| Amount, thus shift on the basis of change impedance.Therefore, selecting 1 duplexer 20 or in the case where 30, also with 2 duplexs of selection Device 20 and the case where 30 similarly, loss caused by high-frequency front-end circuit 1 is able to suppress because of impedance mismatch, therefore can be realized Low-loss.

[2. embodiment]

In the following, high-frequency front-end circuit 1 involved in present embodiment is described in detail using specific embodiment.

Fig. 7 is the figure for indicating to support the characteristic of the single duplexer 20 of Band26 in embodiment.Specifically, the figure (a) be single duplexer 20 structure chart.(b) of the figure is the chart for indicating the bandpass characteristics of single duplexer 20, is shown Insertion loss (solid line in figure) and B26Com terminal between B26Tx terminal 102Tx and B26Com terminal 102Com Insertion loss (dotted line in figure) between 102Com and B26Rx terminal 102Rx.(c-1) of the figure indicates B26Tx band The impedance operator of the B26Tx terminal 102Tx of the impedance operator (solid line in figure) and B26Tx band of B26Com terminal 102Com The Smith chart of (dotted line in figure).(c-2) of the figure is the impedance operator for indicating the B26Com terminal 102Com of B26Rx band The Smith chart of the impedance operator (dotted line in figure) of the B26Rx terminal 102Rx of (solid line in figure) and B26Rx band.? This, above-mentioned B26Com terminal 102Com is the public terminal of duplexer 20.

Fig. 8 is the figure for indicating to support the characteristic of the single duplexer 30 of Band12 in embodiment.Specifically, the figure (a) be single duplexer 30 structure chart.(b) of the figure is the chart for indicating the bandpass characteristics of single duplexer 30, is shown Insertion loss (solid line in figure) and B12Com terminal between B12Tx terminal 103Tx and B12Com terminal 103Com Insertion loss (dotted line in figure) between 103Com and B12Rx terminal 103Rx.(c-1) of the figure indicates B12Tx band The impedance operator of the B12Tx terminal 103Tx of the impedance operator (solid line in figure) and B12Tx band of B12Com terminal 103Com The Smith chart of (dotted line in figure).(c-2) of the figure is the impedance operator for indicating the B12Com terminal 103Com of B12Rx band The Smith chart of the impedance operator (dotted line in figure) of the B12Rx terminal 103Rx of (solid line in figure) and B12Rx band.? This, above-mentioned B12Com terminal 103Com is the public terminal of duplexer 30.

As shown in fig. 7, the impedance of single duplexer 20, specifically in terms of B26Com terminal 102Com when the impedance exist Capacitive character is presented in i.e. Band26 in the passband of duplexer 20.In addition, as shown in figure 8, the impedance of single duplexer 30, specifically Capacitive character is presented in i.e. Band12 in the passband of duplexer 30 in impedance when saying in terms of B12Com terminal 103Com.In this reality It applies in example, these impedances are located at the roughly the same region on Smith chart.That is, the impedance of single duplexer 20 with The impedance of single duplexer 30 is designed to same.Therefore, the electricity of the susceptance ingredient of single duplexer 20 and single duplexer 30 Ingredient of receiving is same.Here, " same " not only includes identical, it also include some errors.

When 2 duplexers 20 and 30 that there will be this characteristic bundle, it is presented below as such characteristic.

Fig. 9 A and Fig. 9 B are the characteristics indicated in the state of bundling 2 duplexers 20 and 30 in embodiment Figure.Specifically, (a) of Fig. 9 A be by the public terminal of duplexer 20 and 30 (that is, B26Com terminal 102Com and B12Com terminal 103Com) structure chart of state that bundles.(b) of Fig. 9 A is indicated the public of duplexer 20 and 30 Terminal bundle in the state of duplexer 20 bandpass characteristics chart, show B26Tx terminal 102Tx and the end Com The insertion between insertion loss (solid line in figure) and Com terminal 101Com and B26Rx terminal 102Rx between sub- 101Com It is lost (dotted line in figure).(c-1) of Fig. 9 A is the impedance operator (reality in figure for indicating the Com terminal 101Com of B26Tx band Line) and B26Tx band B26Tx terminal 102Tx impedance operator (dotted line in figure) Smith chart.(c-2) of Fig. 9 A It is the B26Rx terminal 102Rx for impedance operator (solid line in figure) and the B26Rx band for indicating the Com terminal 101Com of B26Rx band Impedance operator (dotted line in figure) Smith chart.(d) of Fig. 9 B is indicated the public terminal bundle of duplexer 20 and 30 The chart of the bandpass characteristics of duplexer 30 in the state of being held together, shows B12Tx terminal 103Tx and Com terminal Insertion damage between insertion loss (solid line in figure) and Com terminal 101Com and B12Rx terminal 103Rx between 101Com It consumes (dotted line in figure).(e-1) of Fig. 9 B is the impedance operator (solid line in figure) for indicating the Com terminal 101Com of B12Tx band And the Smith chart of the impedance operator (dotted line in figure) of the B12Tx terminal 103Tx of B12Tx band.(e-2) of Fig. 9 B is table Show the resistance of the impedance operator (solid line in figure) of the Com terminal 101Com of B12Rx band and the B12Rx terminal 103Rx of B12Rx band The Smith chart of anti-characteristic (dotted line in figure).Here, above-mentioned Com terminal 101Com is by the end B26Com of duplexer 20 The terminal that sub- 102Com is bundled with the B12Com terminal 103Com of duplexer 30 and (connect jointly).

As shown in fig. 9 a and fig. 9b, impedance, tool in the state of the public terminal of duplexer 20 and 30 being bundled Impedance when saying to body in terms of Com terminal 101Com is in the passband of duplexer 20 in the passband of i.e. Band26 and duplexer 30 That is capacitive character is presented in this two side of Band12.Specifically, the impedance is located at the impedance compared to single duplexer 20 (referring to figure 7 (c-1) and (c-2)) and single duplexer 30 impedance (referring to (c-1) and (c-2) of Fig. 8) etc. conductances justify and (do not scheme Show) on deasil shift after region.That is, the impedance in the state of bundling has and single duplexer The comparable susceptance ingredient of aggregate value of the susceptance ingredient under susceptance ingredient and single duplexer 30 under 20.

In the high-frequency front-end circuit involved in the present embodiment with this characteristic, by capacitor C (the first impedance element Part) capacitance be set as 5.8pF, the inductance value of inductor L (the second impedor) is set as 3.7nH.

In the following, the characteristic of the high-frequency front-end circuit involved in embodiment, illustrates that selecting multiple equipment (is herein 2 Duplexer 20 and 30) when characteristic (characteristic when CA of Band26 and Band12) and selection single equipment when characteristic (i.e. characteristic when the non-CA of characteristic and Band12 when the non-CA of Band26).

Figure 10 A and Figure 10 B are when indicating the CA of Band26 and Band12 in the high-frequency front-end circuit involved in embodiment Characteristic figure.Specifically, (a) of Figure 10 A is the knot of high-frequency front-end circuit involved in embodiment when obtaining the characteristic Composition, main switch SW1 and main switch SW2 are turned on, and auxiliary switch SW1g and auxiliary switch SW2g are disconnected.(b) of Figure 10 A is to indicate The chart of the bandpass characteristics of high-frequency front-end circuit involved in embodiment at this time shows B26Tx terminal 102Tx and the end ANT The insertion loss between insertion loss (solid line in figure) and ANT terminal 101 and B26Rx terminal 102Rx between son 101 (dotted line in figure).(c-1) of Figure 10 A be indicate the ANT terminal 101 of B26Tx band impedance operator (solid line in figure) and The Smith chart of the impedance operator (dotted line in figure) of the B26Tx terminal 102Tx of B26Tx band.(c-2) of Figure 10 A is to indicate The impedance of the B26Rx terminal 102Rx of the impedance operator (solid line in figure) and B26Rx band of the ANT terminal 101 of B26Rx band is special The Smith chart of property (dotted line in figure).(d) of Figure 10 B is high-frequency front-end circuit involved in the embodiment that indicates at this time The chart of bandpass characteristics, show insertion loss (solid line in figure) between B12Tx terminal 103Tx and ANT terminal 101 and Insertion loss (dotted line in figure) between ANT terminal 101 and B12Rx terminal 103Rx.(e-1) of Figure 10 B is to indicate B12Tx Impedance operator (the figure of the B12Tx terminal 103Tx of the impedance operator (solid line in figure) and B12Tx band of the ANT terminal 101 of band In dotted line) Smith chart.(e-2) of Figure 10 B is to indicate the impedance operator of the ANT terminal 101 of B12Rx band (in figure Solid line) and B12Rx band B12Rx terminal 103Rx impedance operator (dotted line in figure) Smith chart.

As shown in figs. 10 a and 10b, in the high-frequency front-end circuit involved in embodiment, select 2 duplexers 20 and In the case where 30, ANT terminal 101, the end B26Tx terminal 103Tx, B26Rx terminal 103Rx, B12Tx terminal 102Tx and B12Rx Sub- 102Rz is matched respectively as 50 Ω as benchmark impedance.

Figure 11 A is the figure of characteristic when indicating the non-CA of Band26 in the high-frequency front-end circuit involved in embodiment. Specifically, (a) of the figure is the structure chart of high-frequency front-end circuit involved in embodiment when obtaining the characteristic, main switch SW1 is connected, and auxiliary switch SW1g is disconnected, and main switch SW2 is disconnected, and auxiliary switch SW2g is connected.(b) of the figure is the implementation indicated at this time The chart of the bandpass characteristics of high-frequency front-end circuit involved in example, shows between B26Tx terminal 102Tx and ANT terminal 101 Insertion loss (dotted line in figure) between insertion loss (solid line in figure) and ANT terminal 101 and B26Rx terminal 102Rx. (c-1) of the figure is the impedance operator (solid line in figure) for indicating the ANT terminal 101 of B26Tx band and the B26Tx of B26Tx band The Smith chart of the impedance operator (dotted line in figure) of terminal 102Tx.(c-2) of the figure is the ANT terminal for indicating B26Rx band The impedance operator (dotted line in figure) of the B26Rx terminal 102Rx of 101 impedance operator (solid line in figure) and B26Rx band Smith chart.

Figure 11 B is the figure of characteristic when indicating the non-CA of Band12 in the high-frequency front-end circuit involved in embodiment, Main switch SW1 is disconnected, and auxiliary switch SW1g is connected, and main switch SW2 is connected, and auxiliary switch SW2g is disconnected.Specifically, (a) of the figure It is the structure chart of high-frequency front-end circuit involved in embodiment when obtaining the characteristic.(b) of the figure is the implementation indicated at this time The chart of the bandpass characteristics of high-frequency front-end circuit involved in example, shows between B12Tx terminal 103Tx and ANT terminal 101 Insertion loss (dotted line in figure) between insertion loss (solid line in figure) and ANT terminal 101 and B12Rx terminal 103Rx. (c-1) of the figure is the impedance operator (solid line in figure) for indicating the ANT terminal 101 of B12Tx band and the B12Tx of B12Tx band The Smith chart of the impedance operator (dotted line in figure) of terminal 103Tx.(c-2) of the figure is the ANT terminal for indicating B12Rx band The impedance operator (dotted line in figure) of the B12Rx terminal 103Rx of 101 impedance operator (solid line in figure) and B12Rx band Smith chart.

As shown in Figure 11 A, when supporting the non-CA of the Band26 of the duplexer 20 of Band26 in selection, ANT terminal 101, B26Tx terminal 102Tx and B26Rx terminal 102Rx is matched respectively as 50 Ω as benchmark impedance.In addition, such as Figure 11 B It is shown, selection support Band12 duplexer 20 Band12 non-CA when, ANT terminal 101, B12Tx terminal 103Tx with And B12Rx terminal 103Rx is matched respectively as 50 Ω as benchmark impedance.

[3. effects etc.]

As described above, according to the present embodiment involved in high-frequency front-end circuit 1, have will select terminal 112 (first Selection terminal) the capacitor C (the first impedor) that is connect with selection terminal 113 (second select terminal).

It is as a result, to only have in main switch SW1 (the first main switch) and main switch SW2 (the second main switch) in switching circuit 10 When the first connection type that one side connects (when in the present embodiment to select single equipment), capacitor C is via auxiliary switch A side in SW1g (the first auxiliary switch) and auxiliary switch SW2g (the second auxiliary switch) is connected to ground.Therefore, capacitor C makees at this time It works for the impedor of impedance matching circuit.It on the other hand, is this two side of main switch SW1 and SW2 in switching circuit 10 When the second connection type connected (when in the present embodiment to select more equipment), the both ends of capacitor C are via main switch SW1 It is short-circuited with main switch SW2.Therefore, capacitor C does not work at this time.That is, according to the present embodiment, without it is additional at For the impedor of impedance matching circuit, impedance matching circuit, therefore energy can be changed according to the connection type of switching circuit It is enough to realize miniaturization and low-loss.

Here, capacitor C only makes the impedance and benchmark of ANT terminal 101 when switching circuit 10 is the first connection type Impedance matching.By being switched according to the first connection type and the second connection type like this whether by capacitor C progress Match, is equal to and (constitutes 2 impedance matching circuits herein using 1 impedor for capacitor C).Therefore, structure can be cut down At the parts number of impedance matching circuit, therefore it can be realized miniaturization.

In addition, high-frequency front-end circuit 1 involved according to the present embodiment, is also equipped with and is connected to ground public terminal 111 Inductor L (the second impedor).

As a result, switching circuit 10 be the first connection type in the case where, can by by capacitor C with inductor L's Parallel circuit constitute impedance matching circuit come make ANT terminal 101 impedance and benchmark impedance matching, be in switching circuit 10 In the case where second connection type, the impedance of ANT terminal 101 can be made by the impedance matching circuit being made of inductor L With benchmark impedance matching.Therefore, no matter switching circuit 10 is the first connection type or the second connection type, can be realized Low-loss.

In addition, high-frequency front-end circuit 1 involved according to the present embodiment, duplexer 20 (first filter) and duplexer 30 (second filters) are acoustic wave filters, (high selection degree) filter characteristic that thus, it is possible to obtain having steepness excellent , small-sized and low clearance duplexer 20 and 30.That is, according to the present embodiment, can be realized and realizing further While miniaturization, the high-frequency front-end circuit 1 of low-loss and high selection degree.

In addition, high-frequency front-end circuit 1 involved according to the present embodiment, the first impedor is capacitor C, the second resistance Anti- element is inductor L.Here, constructively, constituting duplexer 20 (first filter) and (the second filtering of duplexer 30 Device) the impedance of acoustic wave filter that capacitive situation is presented is more.Therefore, by by capacitor C be used as the first impedor, Inductor L is used as the second impedor, no matter switching circuit 10 is the first connection type or the second connection type, can Make the impedance and benchmark impedance matching of ANT terminal 101, therefore can be realized low-loss.That is, according to this embodiment party Formula can be realized while realizing miniaturization, the high-frequency front-end circuit 1 of low-loss and high selection degree.

In addition, high-frequency front-end circuit 1 involved according to the present embodiment, single duplex when being seen from selection terminal 112 Susceptance ingredient in the passband of device 20 (first filter) and (the second filtering of single duplexer 30 when being seen from selection terminal 113 Device) passband in susceptance ingredient it is same.As a result, no matter switching circuit 10 be only main switch SW1 connect the first connection side When formula, when the first connection type that still only main switch SW2 is connected, building-out condenser C (the first impedance element can be passed through Part) so that the impedance of ANT terminal 101 is displaced to the roughly the same position on Smith chart.I.e. it is capable to make ANT The admittance of terminal 101 is displaced to the roughly the same position on dmittance chart.Therefore, pass through the constant of appropriate adjustment capacitor C, nothing By be which kind of above-mentioned situation can make ANT terminal 101 impedance and benchmark impedance matching.Therefore, it is able to suppress component count The increase of amount, therefore can be realized further miniaturization.

In addition, high-frequency front-end circuit 1 involved according to the present embodiment, at least one in duplexer 20 and duplexer 30 Side's (being in the present embodiment both sides) is made of multiple filters, therefore for example can be realized the transmitting and receiving for supporting CA High-frequency front-end circuit.

(variation 1 of embodiment 1)

In the above-described embodiment, first filter and second filter are duplexers.It therefore, can be by single first Susceptance ingredient in the passband of filter and the susceptance ingredient in the passband of single second filter are designed as on an equal basis.With this phase Right, in this variation, first filter is made of 1 filter, and second filter is the duplex being made of 2 filters Device.Therefore, when first filter and second filter are utilized respectively acoustic wave filter to constitute, it is difficult to by single first Susceptance ingredient in the passband of filter and the susceptance ingredient in the passband of single second filter are designed as on an equal basis, and single first The susceptance ingredient of filter is less than the susceptance ingredient of single second filter.In this variation, illustrate this high frequency front-end electricity Road.

Figure 12 is the structure chart of high-frequency front-end circuit 1A involved in the variation 1 of embodiment 1.

Compared to high-frequency front-end circuit 1 involved in above embodiment, high-frequency front-end circuit 1A shown in the figure is supported It replaces supporting Band26 as the Band29 for receiving dedicated Band, and supports to be able to carry out the Band5 with the CA of Band29 To replace supporting Band12.Therefore, in high-frequency front-end circuit 1A, as first filter, has the filtering for supporting Band29 Device 40 replaces supporting the duplexer 20 of Band26 have and the duplexer 50 of Band5 is supported to replace propping up as second filter Hold the duplexer 30 of Band12.

Filter 40 is the receiving filter of the Rx band including Band29 in the pass-band.One input of the filter 40 is defeated Terminal (being herein input terminal) is connect with the selection terminal 112 of switching circuit 10 out, another input and output terminal (herein for Output terminal) it is connect with B29Rx terminal 104Rx.

Duplexer 50 is made of transmitting filter 51 and receiving filter 52, which includes in the pass-band The Tx band of Band5, and including the Rx band of Band5 in attenuation band, which includes the Rx of Band5 in the pass-band Band, and including the Tx band of Band5 in attenuation band.One input and output terminal of the transmitting filter 51 (is herein output end Son) and the receiving filter 52 an input and output terminal (being herein input terminal) jointly connect (binding) in duplexer 50 Public terminal after, connect with the selection terminal 113 of switching circuit 10.In addition, another input and output of transmitting filter 51 Terminal (being herein input terminal) is connect with B5Tx terminal 105Tx.In addition, another input and output terminal of receiving filter 52 (being herein output terminal) connect with B5Rx terminal 105Rx.

In the present embodiment, these filters 40 and duplexer 50 (first filter and second filter) are by elasticity The acoustic wave filter that wave resonator is constituted.Specifically, constituting the transmitting filter 51 and receiving filter 52 of duplexer 50 It is acoustic wave filter respectively.Therefore, the susceptance ingredient for the single filter 40 being made of 1 acoustic wave filter is less than by 2 The susceptance ingredient for the single duplexer 50 that a acoustic wave filter is constituted.

Therefore, high-frequency front-end circuit 1A involved in this variation is suitable with the capacitor C in embodiment 1 in addition to having Capacitor C1 (the first impedor) other than, terminal 112 (first choice terminal) capacitor for being connected to ground will be selected by being also equipped with Device C2 (third impedor).Capacitor C2 is constituted together with inductor L or also together with capacitor C2 makes ANT terminal 101 impedance and the impedance matching circuit of benchmark impedance matching.In the following, the feelings are described in detail using Figure 13 A~Figure 15 B Condition.

Figure 13 A is this variation schematically shown when selecting multiple equipment (being herein filter 40 and duplexer 50) The figure of the structure of related high-frequency front-end circuit 1A.Figure 13 B is the equivalent circuit diagram of Figure 13 A.

As shown in these figures, in the case where selecting filter 40 and duplexer 50, the both ends of capacitor C1 are via 2 masters Switch SW1 and SW2 are short-circuited.Therefore, in this case, capacitor C1 does not work, selected filter 40 and duplexer By inductor L (the second impedor) with capacitor C2 (third impedance element between the terminal and ground of 50 101 side of ANT terminal Part) parallel circuit connect.That is, switching circuit 10 be the second connection type (that is, main switch SW1 and SW2 this two Side connects) when, inductor L makes the impedance and benchmark impedance matching of ANT terminal 101 with the parallel circuit of capacitor C2.Change speech It, at this point, impedance matching circuit is made of above-mentioned parallel circuit.

Figure 14 A is to schematically show this variation for selecting filter 40 (first filter) as single equipment when The figure of the structure of related high-frequency front-end circuit 1A.Figure 14 B is the equivalent circuit diagram of Figure 14 A.

As shown in these figures, only select 1 filter 40 in the case where, capacitor C1 via with non-selected duplexer 50 corresponding auxiliary switch SW2g are connected to ground.Therefore, in this case, 101 side of ANT terminal of selected filter 40 Pass through capacitor C1 (the first impedor) between terminal and ground with capacitor C2 (third impedor) with inductor L (second Impedor) parallel circuit connect.That is, being that only main switch SW1 (the first main switch) connects in switching circuit 10 When logical first connection type, capacitor C1 with capacitor C2 with the parallel circuit of inductor L make the impedance of ANT terminal 101 with Benchmark impedance matching.In other words, at this point, impedance matching circuit is made of above-mentioned parallel circuit.

Figure 15 A is to schematically show this variation for selecting duplexer 50 (second filter) as single equipment when The figure of the structure of related high-frequency front-end circuit 1A.Figure 15 B is the equivalent circuit diagram of Figure 15 A.

As shown in these figures, only select 1 duplexer 50 in the case where, capacitor C1 via with non-selected filter 40 corresponding auxiliary switch SW1g are connected to ground.Therefore, in this case, 101 side of ANT terminal of selected duplexer 50 Connected by capacitor C1 (the first impedor) with the parallel circuit of inductor L (the second impedor) between terminal and ground It connects.That is, when switching circuit 10 is only first connection type of main switch SW2 (the second main switch) connection, capacitor Device C1 makes the impedance and benchmark impedance matching of ANT terminal 101 with the parallel circuit of inductor L.In other words, at this point, impedance Distribution routes above-mentioned parallel circuit and constitutes.

In this way, according to this modification, the case where selecting more equipment can be directed to, select first filter as single equipment The case where and select the case where second filter is as single equipment, Lai Biangeng impedance matching (impedance matching circuit).

In the following, illustrating the principle of the impedance matching in this variation.

Figure 16 is the Smith chart for illustrating the impedance matching in this variation.

Constructively, capacitor is presented in the filter 40 being made of acoustic wave filter and the respective impedance of duplexer 50 Property, compared with the duplexer 50 being made of 2 filters (transmitting filter 51 and receiving filter 52), by 1 filter structure At filter 40 small capacitive character is presented.Specifically, (hereinafter referred to as " Filter monomer is special for the impedance of single filter 40 Property ") be designed to be expressed as the gable of " Filter monomer properties " on the Smith chart of Figure 16.In addition, single The impedance (hereinafter referred to as " DPX monomer properties ") of duplexer 50 is designed to be expressed as that " DPX is mono- on the Smith chart of Figure 16 The rectangle part of bulk properties ".

Therefore, the impedance obtained after the public terminal of filter 40 and duplexer 50 this two side being connected jointly is (referred to below as For " Filter+DPX bundlees characteristic ") it is located at the circle that " Filter+DPX bundlees characteristic " is expressed as on the Smith chart of Figure 16 Shape part.

Thus, by characteristic when being made of 1 filter i.e. " Filter monomer properties ", be made of 2 filters when The characteristic i.e. sequence of " Filter+DPX bundlees characteristic " when characteristic is " DPX monomer properties ", is made of 3 filters, susceptance Ingredient successively becomes larger.This is because, in the passband (from frequency band) of itself, the filter bundled is attenuation band, therefore conduct Capacitor works, and therefore, the more more then susceptance ingredients of the filter of binding are bigger.

In this variation, can be for only selection filter 40 the case where, only selects the case where duplexer 50 and choosing The situation of filter 40 and duplexer 50 this two side is selected to change impedance matching (impedance matching circuit), therefore can be realized small-sized Change.

Specifically, the capacitance of capacitor C1 and C2 and the inductance value of inductor L are for example configured to satisfaction or less Formula.

B₁₁+|j2πfC₂|=|-j (1/ (2 π fL)) |

B₁₂+|j2πfC₁|=|-j (1/ (2 π fL)) |

B₁₃+|j2πf(C₁+C₂) |=|-j (1/ (2 π fL)) |

Here, B₁₁、B₁₂、B₁₃Be sequentially the Filter+DPX binding susceptance value of characteristic, the susceptance value of DPX monomer properties, The susceptance value of Filter monomer properties.In addition, C₁、C₂, L be sequentially the capacitance of capacitor C1, the capacitance of capacitor C2, electricity The inductance value of sensor L.In addition, f is such as centre frequency of passband.In addition, B₁₁> B₁₂> B₁₃, therefore C₂< C₁Relationship at It is vertical.

As a result, according to this modification, without the additional impedor for becoming impedance matching circuit, matching 3 can be constituted The impedance matching circuit of impedance state (Filter+DPX bundlees characteristic, DPX monomer properties, Filter monomer properties).

In this way, high-frequency front-end circuit 1A involved according to this modification, (the first choice end of terminal 112 will be selected by having Son) the capacitor C1 (the first impedor) that is connect with selection terminal 113 (second selection terminal), thus together with embodiment 1 It can be realized to sample miniaturization and low-loss.

In addition, high-frequency front-end circuit 1A involved according to this modification, 112 (first choice of terminal will be selected by being also equipped with Terminal) the capacitor C2 (third impedor) that is connected to ground, even the thus electricity of single filter 40 (first filter) Ingredient of receiving is less than the case where susceptance ingredient of single duplexer (second filter), also can be according to the connection type of switching circuit Impedance matching circuit is changed, therefore can be realized miniaturization and low-loss.

This structure is particularly useful in the case where high-frequency front-end circuit 1A is following structure.That is, switching circuit 10 has There are 3 or more selection terminals, high-frequency front-end circuit 1A, which is also equipped with, has the susceptance bigger than the susceptance ingredient of single duplexer 50 The equipment (for example, the multiplexers such as duplexer) of ingredient.Here, on the road for linking the selection terminal of the equipment and switching circuit 10 Without connection impedor on diameter, and the equipment is only made monomer with (choosing).

In this configuration, by being set to the inductance value of inductor L to obtain impedance when selecting the equipment Match, 4 impedance state (Filter of matching can be constituted using 3 impedors (capacitor C1, capacitor C2, inductor L) + DPX bundle characteristic, DPX monomer properties, Filter monomer properties, above equipment monomer properties) impedance matching circuit.

In particular, in this variation, the first impedor (capacitor C1) and the second impedor (capacitor C2) are The capacitance of capacitor, third impedor is smaller than the capacitance of the first impedor.As a result, in single filter 40 and individually Single filter 40 and single duplexer 50 divide when susceptance ingredient in the respective passband of duplexer 50 is greater than j0, in passband Not Cheng Xian capacitive character when, can be realized miniaturization and low-loss.

(variation 2 of embodiment 1)

In addition, replacing will select in the variation 1 of above embodiment 1 by using the breaking capacitance of auxiliary switch SW1g The capacitor C2 that terminal 112 is connected to ground is selected, identical effect can be played.Therefore, in this variation, illustrate this high frequency Front-end circuit.

Figure 17 is the structure chart of high-frequency front-end circuit 1B involved in the variation 2 of embodiment 1.In addition, in the figure The breaking capacitance of breaking capacitance and auxiliary switch SW2g (the second auxiliary switch) also to auxiliary switch SW1g (the first auxiliary switch) carries out Diagram.Here, the breaking capacitance of switch, which refers to, is switching the capacitor disconnected when between switch terminal.For example, auxiliary switch The breaking capacitance of SW1g be when auxiliary switch SW1g is disconnected the first terminal for being connected to selection terminal 112 be connected to the of ground The capacitor generated between two-terminal.

Compared with the high-frequency front-end circuit 1A involved in the variation 1 of above embodiment 1, high frequency front-end shown in the figure Circuit 1B is different in the following areas: not having capacitor C2 (third impedor), the breaking capacitance of auxiliary switch SW1g is opened than pair The breaking capacitance for closing SW2g is big.

Specifically, the capacitance of capacitor C1, the capacitance of the breaking capacitance of auxiliary switch SW1g, auxiliary switch SW2g's is disconnected The inductance value of the capacitance and inductor L of opening capacitor is for example configured to meet the following formula.

B₁₁+|j2πf(C_off1+C_off2) |=|-j (1/ (2 π fL)) |

B₁₂+|j2πf(C₁+C_off2) |=|-j (1/ (2 π fL)) |

B₁₃+|j2πf(C₁+C_off1) |=|-j (1/ (2 π fL)) |

Here, B₁₁、B₁₂、B₁₃Be sequentially the Filter+DPX binding susceptance value of characteristic, the susceptance value of DPX monomer properties, The susceptance value of Filter monomer properties.In addition, C₁、L、C_off1、C_off2It is sequentially the inductance of the capacitance of capacitor C1, inductor L Capacitance, the capacitance of the breaking capacitance of auxiliary switch SW2g of value, the breaking capacitance of auxiliary switch SW1g.In addition, f is the example of passband Such as centre frequency.In addition, B₁₁> B₁₂> B₁₃, therefore C_off2< C_off1Relationship set up.

That is, according to this modification, in the case where selecting filter 40 and duplexer 50, selected filter 40 and duplexer 50 101 side of ANT terminal terminal and ground between pass through the breaking capacitance of auxiliary switch SW1g (the first auxiliary switch) Breaking capacitance with auxiliary switch SW2g (the second auxiliary switch) is connected with the parallel circuit of inductor L (the second impedor).Separately Outside, in the case where only selecting 1 duplexer 50, lead between the terminal and ground of 101 side of ANT terminal of selected duplexer 50 It crosses capacitor C1 (the first impedor) and is connected with the breaking capacitance of auxiliary switch SW2g with the parallel circuit of inductor L.In addition, In the case where only selecting 1 filter 40, pass through between the terminal and ground of 101 side of ANT terminal of selected filter 40 Capacitor C1 is connected with the breaking capacitance of auxiliary switch SW1g with the parallel circuit of inductor L.

Even if high-frequency front-end circuit 1B involved in this variation being formed by, can also play and above-mentioned embodiment party The identical effect of variation 1 of formula 1.That is, without the additional impedor for becoming impedance matching circuit, it can be for only The case where selecting filter 40, the situation for only selecting the case where duplexer 50 and selection this two side of filter 40 and duplexer 50 To change impedance matching (impedance matching circuit).

In addition, the disconnection of high-frequency front-end circuit 1B, auxiliary switch SW1g (the first auxiliary switch) involved according to this modification The breaking capacitance of capacity ratio auxiliary switch SW2g (the second auxiliary switch) is big, thus, it is possible to cut down the number of impedor and play with it is upper The identical effect of variation 1 of embodiment 1 is stated, therefore can be realized further miniaturization.

(embodiment 2)

The structure of the high-frequency front-end circuit illustrated in above embodiment 1 and its variation can be applied to support more The high-frequency front-end circuit of frequency range.

Figure 18 is the structure chart of high-frequency front-end circuit 100 involved in embodiment 2.

High-frequency front-end circuit 100 shown in the figure has: the switch with public terminal 111 and selection terminal 112~115 Circuit 110；Filter 120；Duplexer 130,140 and 150；Inductor L (the second impedor)；And capacitor C11~C14 (the first impedor).

Filter 120 includes the Rx band of Band29 in the pass-band, is connect with selection terminal 112.Duplexer 130 is in the pass-band Tx band and Rx band including Band12 and Band17 are connect with selection terminal 113.Duplexer 140 includes Band13 in the pass-band With the Tx band and Rx band of Band14, it is connect with selection terminal 114.Duplexer 150 includes the Tx band and Rx of Band26 in the pass-band Band is connect with selection terminal 115.

Capacitor C11 will select terminal 112 to connect with selection terminal 115, and capacitor C12 will select terminal 113 and selection Terminal 115 connect, capacitor C13 by select terminal 114 with selection terminal 115 connect, capacitor C14 will select terminal 112 and Terminal 113 is selected to connect.

Here, switching circuit 110 has main switch SW11~SW14, main switch SW11~SW14 and selection terminal 112 ~115 independently correspond to, and will be switched between public terminal 111 and corresponding selection terminal 112~115 by switching on and off For connection and it is disconnected.In addition, switching circuit 110 also has auxiliary switch SW11g~SW14g, auxiliary switch SW11g~SW14g It is independently corresponding with selection terminal 112~115, by with the switched on and off mutually exclusive connection of corresponding main switch and disconnected Open, will be switched between corresponding selection terminal 112~115 and ground connection and it is disconnected.

Even if high-frequency front-end circuit 100 involved in the present embodiment being formed by can also play and above-mentioned reality Apply the identical effect of mode 1.That is, even if be have 3 or more equipment (in the present embodiment, be include filtering 4 equipment of device 120 and duplexer 130,140 and 150) high-frequency front-end circuit 100, become impedance matching without additional The impedor of circuit, but (in the present embodiment, can be 4 selection ends by 3 or more selection terminals by being arranged Son 112~115) in it is any 2 selection terminal connection the first impedor (in the present embodiment, for capacitor C11~ C14) come to change impedance matching circuit according to the connection type of switching circuit 110, therefore can be realized miniaturization and low-loss.

(embodiment 3)

The high-frequency front-end circuit illustrated in above embodiment 1,2 and its variation can also have and can change passband Or the tunable filter of the frequency of attenuation band etc. is as at least one filter.

Figure 19 is the structure chart of high-frequency front-end circuit 100A and its peripheral circuit involved in embodiment 3.In the figure Show high-frequency front-end circuit 100A, antenna element 2 and RF signal processing circuit (RFIC) 3.High-frequency front-end circuit 100A, day Thread elements 2 and RFIC 3 constitute communication device 4.Antenna element 2, high-frequency front-end circuit 100A and RFIC 3 are for example configured at Support the front end of multi-mode/multiband portable phone.

Antenna element 2 is to transmit and receive high-frequency signal, such as the day of the support multiband according to communication standard LTE Line.Whole frequency ranges of communication device 4 are supported in addition, antenna element 2 for example may not be, can also only support low-frequency band The frequency range of group or high frequency band group.In addition, antenna element 2 can not also be built in communication device 4, but it is independent with communication device 4 Ground setting.

RFIC 3 is the RF signal processing circuit handled the high-frequency signal transmitted and received using antenna element 2.Tool It says to body, RFIC 3 is to the high-frequency reception inputted from antenna element 2 via the receiving side signal path of high-frequency front-end circuit 100A Signal carries out signal processing by down coversion etc., and the reception signal generated after the signal processing is output to base band signal process electricity Road (not shown).In addition, RFIC 3 carries out signal by up-conversion etc. to the transmission signal inputted from baseband signal processing circuit The high frequency generated after the signal processing transmission signal is output to the sending side signal path of high-frequency front-end circuit 100A by processing (not shown).

High-frequency front-end circuit 100A is the circuit that high-frequency signal is transmitted between antenna element 2 and RFIC 3.Specifically, The high frequency exported from RFIC 3 is sent signal and is transmitted to via sending side signal path (not shown) by high-frequency front-end circuit 100A Antenna element 2.In addition, high-frequency front-end circuit 100A is by the high-frequency received signal received using antenna element 2 via receiving side Signal path is transmitted to RFIC 3.

High-frequency front-end circuit 100A successively has inductor L (the second impedor), switching circuit from 2 side of antenna element 110, filter 120A, 130A, 140A and 150A, switch 180A and 180B and reception amplifying circuit group 190.In addition, high frequency Front-end circuit 100A is also equipped with capacitor C21 (the first impedor) and capacitor C22 and C23 (third impedor).

In the present embodiment, switching circuit 110 makes main switch SW11 according to the control signal psi CTL from RFIC 3 ~SW14 and auxiliary switch SW11g~SW14g are switched on and off.That is, in the present embodiment, RFIC 3 is as below Control unit functions: so that 110 second connection type of switching circuit (is made 2 or more main switches simultaneously when carrying out CA Connect), 110 first connection type of switching circuit (only connecting 1 main switch) is made when carrying out non-CA.In addition, can also To be provided independently from control unit with RFIC 3.

Filter 120A, 130A, 140A are made of tunable filter, the filter structure that filter 150A is fixed by frequency At.Specifically, filter 120A is can to support (i) Band29, (ii) Band12 and Band17 or (iii) Band13 With the tunable filter of the high-frequency received signal of Band14, it is connect with selection terminal 112.Filter 130A is can to support (i) The tunable filter of the high-frequency received signal of Band28 or (ii) Band20 is connect with selection terminal 113.Filter 140A is energy The tunable filter of enough high-frequency received signals for supporting (i) Band27 or (ii) Band26 is connect with selection terminal 114.Filtering Device 150A is the filter for supporting that the frequency of the high-frequency received signal of Band8 is fixed, is connect with selection terminal 115.

Switch 180A and 180B will be by that will support the filter of regulation frequency range according to the control signal from control unit (not shown) Be attached with the reception amplifying circuit for receiving the support regulation frequency range in amplifying circuit group 190 1 's or more of wave device opens (being in the present embodiment multiple switch) is closed to constitute.In addition, it is not limited to 1 with the filter that amplifying circuit is connect is received, It can be multiple.

Amplifying circuit group 190 is received by carrying out power amplification to the high-frequency received signal inputted from switch 180A and 180B 1 or more low-noise amplifier (being in the present embodiment multiple low-noise amplifiers) is constituted.

The high-frequency front-end circuit 100A constituted in this way is by the defined filtering of the high-frequency received signal inputted from antenna element 2 After device is filtered and is amplified with defined low-noise amplifier, it is output to RFIC 3.In addition it is also possible to will support low The RFIC of frequency range and the RFIC of support high band are arranged each independently.

Here, capacitor C21 by select terminal 112 with selection terminal 114 connect, capacitor C22 will select terminal 113 and Ground connection, capacitor C23 will select terminal 115 to be connected to ground.

Even if high-frequency front-end circuit 100A involved in the present embodiment being formed by can also be played and above-mentioned reality Apply the identical effect of mode 2.

In addition, filter 120A, 130A and 140A of high-frequency front-end circuit 100A are made of tunable filter, thus with set The case where setting the filter that frequency is fixed can be realized further miniaturization compared to the number that can be cut filter.

In addition, in the present embodiment, as high-frequency front-end circuit 100A, illustrating to be arranged on receiving side signal path There is the structure of the reception diversity of multiple filters (receiving filter).But the structure of high-frequency front-end circuit is without being limited thereto, It can be the structure that the transmission diversity of multiple filters (transmitting filter) is provided on the signal path of sending side.

(other embodiment)

More than, Embodiments 1 to 3 are listed to carry out to high-frequency front-end circuit involved in embodiments of the present invention Illustrate, but the present invention is not limited to above embodiment.Arbitrary structural element in above embodiment is combined Come realize other embodiment, implement those skilled in the art to above embodiment in the model for not departing from spirit of the invention The various modifications expected in enclosing obtain variation, be built-in with the various equipment of high-frequency front-end circuit according to the present invention Comprising in the present invention.

For example, the communication device 4 for having above-mentioned high-frequency front-end circuit and RFIC 3 (RF signal processing circuit) also includes In the present invention.According to this communication device 4, miniaturization and low-loss can be realized.

In addition, in the above description, the end as the high-frequency front-end circuit that the public terminal 111 with switching circuit 10 is connect Son is illustrated by taking the ANT terminal 101 connecting with antenna element as an example.But the high frequency being connect with public terminal 111 The terminal of front-end circuit is not limited to the terminal connecting with antenna element, is also possible to and the reception amplifying circuits such as low-noise amplifier The input and output terminal (being herein output terminal) of connection or the input and output being connect with transmission amplifying circuits such as power amplifiers Terminal (being herein input terminal).That is, multiple filters are connected obtained multiplexer jointly using switching circuit Also it is contained in the present invention.

In addition, for example, high-frequency front-end circuit can also have above explained by first switch circuit and the first impedance It is attached obtained structure to the circuit stages that circuit is constituted.

The structure chart for the high-frequency front-end circuit 100B that Figure 20 is formed by.

High-frequency front-end circuit 100B shown in the figure has the first order circuit for being respectively provided with switching circuit 10 and capacitor C 11 and the second level circuit 12A and 12B.Here, first order circuit 11 is located at that public terminal 111 is connect with ANT terminal 101 Level-one, the second level circuit 12A and 12B are located at public terminal 111 and connect via first order circuit 11 with ANT terminal 101 The second level.

Specifically, first order circuit 11 has: with above explained first switch circuit it is comparable, as second switch The switching circuit 10 of an example of circuit；And it is comparable, as the 4th impedor with above explained first impedor The capacitor C of an example.Selection terminal 112 possessed by switching circuit 10 selectively with it is public possessed by the switching circuit 10 One party connection in terminal 111 and ground terminal.In addition, switching circuit 10 possessed by selection terminal 113 selectively with this One party connection in public terminal 111 and ground terminal possessed by switching circuit 10.

In addition, second level circuit 12A has as the switching circuit 10 of first switch circuit and as the first impedor Capacitor C, with the filter 220A of an example as first filter and the filter of an example as second filter 230A connection.In addition, second level circuit 12B has as the switching circuit 10 of first switch circuit and as the first impedor Capacitor C, with another filter 220B as first filter and as another filtering of second filter Device 230B connection.That is, high-frequency front-end circuit 100B has multiple groups (being herein 2 groups), each group has first switch circuit, first Filter, second filter and the first impedor.

Here, the switch electricity as first switch circuit of the second level circuit 12A in a group in above-mentioned multiple groups Public terminal 111 possessed by road 10 is connect with selection terminal 112 possessed by the switching circuit 10 of first order circuit 11.Separately Outside, the switching circuit 10 as first switch circuit of the second level circuit 12B in another group in above-mentioned multiple groups is had Some public terminals 111 are connect with selection terminal 113 possessed by the switching circuit 10 of first order circuit 11.

In addition, the capacitor C as the 4th impedor of first order circuit 11 is connected to the choosing of first order circuit 11 Select node on the path that the public terminal 111 of terminal 112 and second level circuit 12A links and by first order circuit 11 The node on path for selecting the public terminal 111 of terminal 113 and second level circuit 12B to link.

According to the high-frequency front-end circuit 100B constituted in this way, 4 can be supported while realizing miniaturization and low-loss A above frequency band (being herein 4 frequency bands).

In addition, the number of the selection terminal of first order circuit is not limited to 2, it is also possible to 3 or more.That is, high frequency front-end Circuit 100B can also have 3 groups or more, have first switch circuit, first filter, second filter and first resistance The group of anti-element.According to the high-frequency front-end circuit 100B constituted in this way, more frequency bands can be supported.

In addition, the first impedor of each group is not limited to identical, can also be different.That is, the first impedor of a group The component value of the first impedor organized with another of component value can also be different, can also originally be exactly a side for inductor And another party is capacitor.

In addition, in the above description, about each switch in main switch and auxiliary switch, illustrate for by switch on and off come Switching connection and disconnected independent switch.But main switch and auxiliary switch can also be by by the selection terminals of switching circuit It is constituted as public terminal, by 1 switch of the public terminal of switching circuit and ground terminal alternatively terminal.

The structure chart for the high-frequency front-end circuit 1C that Figure 21 is formed by.

Compared with the switching circuit 10 in above embodiment 1, switching circuit 10C shown in the figure has to be come with lower switch It, will selection terminal 112 (the instead of main switch SW1 and SW2 and auxiliary switch SW1g and SW2g: switch SW11c (first switch) One selection terminal) selectively it is connect with the one party in public terminal 111 and ground terminal 112g；And switch SW12c (second Switch), will selection terminal 113 (second selection terminal) selectively with it is a certain in public terminal 111 and ground terminal 113g Side's connection.Specifically, switch SW11c has the public terminal 112c connecting with selection terminal 112, connects with public terminal 111 The selection terminal 111a connect the and ground terminal 112g being connected to ground, by public terminal 112c selectively with selection terminal 111a And the one party connection in ground terminal 112g.Switch SW12c has the public terminal 113c connecting with selection terminal 113 and public affairs The selection terminal 111b that terminal 111 the connects altogether and ground terminal 113g that is connected to ground, by public terminal 113c selectively with Select the one party connection in terminal 111b and ground terminal 113g.

Even if the high-frequency front-end circuit 1C being formed by, also (the first choice end of terminal 112 can will be selected by having Son) come and above explained high frequency with the capacitor C1 (the first impedor) for selecting terminal 113 (the second selection terminal) to connect Front-end circuit similarly realizes miniaturization and low-loss.In addition, according to the high-frequency front-end circuit 1C constituted in this way, with switch electricity Road 10 is compared, and can reduce the quantity for constituting the switch of switching circuit 10C, therefore can be realized miniaturization.

In addition, for example, capacitor is also possible to DTC (Digital Tunable Capacitor: digital tunable capacitor Device) or apply the varactor capacitor of MEMS or use BST (Ba_1-xSr_xTiO₃: barium strontium titanate) can power transformation Container or varactor.In addition, for example, inductor is also possible to use the variometer of MEMS.

Thereby, it is possible to improve the precision of impedance matching, therefore it can be realized further low-loss.In addition, without increasing Add the number of impedor that can constitute the impedance matching circuit for matching more impedance states, therefore can be in miniaturization The matching of more filters is supported simultaneously.

In addition, filter is not limited to acoustic wave filter, it is also possible to LC filter or dielectric filter.Therefore, single Capacitive character may not be presented in the impedance operator of a filter.Therefore, the first impedor or third impedor are not limited to capacitor, It is also possible to inductor, the second impedor is also possible to capacitor.

In addition, the impedance obtained after bundling first filter and second filter only has real component When situation, such as the case where the impedance of single first filter and the impedance of single second filter are in conjugate relation etc. When, the second impedor can also be not provided with.

In addition, benchmark impedance is not limited to 50 Ω, such as can be according to the communication device of application high-frequency front-end circuit etc. It is required that specification etc. is suitably set.

It include passing through between each structural element in addition, being for example also possible in high-frequency front-end circuit or communication device The inductor or transmission line that the wiring connected between each structural element is generated.

Industrial availability

It is logical can be widely used in portable phone etc. as small-sized and low-loss front-end circuit and communication device by the present invention Believe equipment.

Description of symbols

1,1A, 1B, 1C, 100,100A: high-frequency front-end circuit；2: antenna element；3:RFIC (RF signal processing circuit)；4: Communication device；10,10C, 110: switching circuit；11: first order circuit；12A, 12B: second level circuit；20,30,50,130, 140,150: duplexer；21,31,51: transmitting filter；22,32,52: receiving filter；40,120,120A,130A,140A, 150A, 220A, 220B, 230A, 230B: filter；101:ANT terminal (input and output terminal)；111,112c, 113c: public Terminal；112~115,111a, 111b: selection terminal；112g, 113g: ground terminal；180A, 180B, SW11c, SW12c: switch； 190: receiving amplifying circuit group；C, C1, C11~C14, C21: capacitor (the first impedor)；C2, C22, C23: capacitor (third impedor)；L: inductor (the second impedor)；SW1, SW2, SW11~SW14: main switch；SW1g,SW2g, SW11g~SW14g: auxiliary switch.

Claims

1. a kind of high-frequency front-end circuit, has:

Switching circuit has the public terminal connecting with input and output terminal and selectively connect with the public terminal Multiple selection terminals；

First filter is connect with the first choice terminal in the multiple selection terminal；

Second filter connect with the second selection terminal in the multiple selection terminal, has and the first filter The different passband of passband；And

First impedor,

Wherein, the switching circuit includes

First main switch will be switched to by switching on and off between the public terminal and the first choice terminal It connects and disconnected；

First auxiliary switch will be described by switched on and off mutually exclusive switched on and off with first main switch Be switched between first choice terminal and ground connection and it is disconnected；

Second main switch, by not switched on and off switching on and off of being restricted by first main switch, by institute State public terminal and it is described second selection terminal between be switched to connection and it is disconnected；And

Second auxiliary switch, by with second main switch is mutually exclusive switches on and off, by the second selection terminal It is switched to and connect and disconnected between ground,

First impedor is connected to the section on the path of the first choice terminal and first filter connection Node on point and the path for linking the second selection terminal and the second filter.

2. high-frequency front-end circuit according to claim 1, which is characterized in that

The first connection type that the switching circuit only has a side to connect in first main switch and second main switch Switch between the second connection type connected with first main switch and this two side of second main switch,

Only in first connection type that the switching circuit is in first connection type and second connection type When, first impedor makes the impedance and benchmark impedance matching of the input and output terminal.

3. high-frequency front-end circuit according to claim 1 or 2, which is characterized in that

The high-frequency front-end circuit is also equipped with the second impedor for being connected to ground the public terminal,

It is first main switch and the first connection side that an only side connects in second main switch in the switching circuit When formula, first impedor makes impedance and the base of the input and output terminal with the parallel circuit of second impedor Standardization impedance matching,

When the switching circuit is the second connection type that first main switch is connected with second main switch this two side, Only have second impedor to make the input and output terminal in first impedor and second impedor Impedance and the benchmark impedance matching.

4. high-frequency front-end circuit according to claim 3, which is characterized in that

The first filter and the second filter are the acoustic wave filters with elastic wave resonator.

5. high-frequency front-end circuit according to claim 4, which is characterized in that

First impedor is capacitor,

Second impedor is inductor.

6. the high-frequency front-end circuit according to any one of claim 3~5, which is characterized in that

Susceptance ingredient in the passband of single first filter when in terms of the first choice terminals side is less than from described Susceptance ingredient in the passband of single second filter when second selection terminals side is seen,

The high-frequency front-end circuit is also equipped with the third impedor for being connected to ground the first choice terminal,

When the switching circuit is first connection type that only described first main switch is connected, first impedance element Part makes impedance and the institute of the input and output terminal with second impedor with the parallel circuit of the third impedor Benchmark impedance matching is stated,

When the switching circuit is first connection type that only described second main switch is connected, first impedance element Part makes the impedance and the benchmark impedance matching of the input and output terminal with the parallel circuit of second impedor,

The switching circuit be second connection type when, second impedor with the third impedor and Connection circuit makes the impedance and the benchmark impedance matching of the input and output terminal.

7. high-frequency front-end circuit according to claim 6, which is characterized in that

The third impedor is capacitor,

In the case where first impedor is capacitor, the capacitance of the third impedor is than first impedance The capacitance of element is small.

8. the high-frequency front-end circuit according to any one of claim 3~5, which is characterized in that

The breaking capacitance of first auxiliary switch is bigger than the breaking capacitance of second auxiliary switch.

9. high-frequency front-end circuit described according to claim 1~any one of 5, which is characterized in that

Susceptance ingredient in the passband of single first filter when in terms of the first choice terminals side with from described the Susceptance ingredient in the passband of single second filter when two selection terminals sides are seen is same.

10. high-frequency front-end circuit described according to claim 1~any one of 9, which is characterized in that

At least one party in the first filter and the second filter is made of multiple filters,

The multiple filter is the multiplexer connecting after a respective terminal is connected jointly with the switching circuit.

11. high-frequency front-end circuit described according to claim 1~any one of 10, which is characterized in that

The high-frequency front-end circuit is also equipped with control unit, and the control unit is carrying out carrier wave polymerization, i.e. while sending or receiving pair The first band of the passband distribution of the first filter and when to the second band of the passband of second filter distribution, Make the switching circuit second connection type, carry out it is non-carrier polymerization, i.e. send or receive the first band and When either in the second band, make the switching circuit first connection type.

12. a kind of high-frequency front-end circuit, has:

Second filter is connect with the second selection terminal in the multiple selection terminal；And

First impedor,

Wherein, the switching circuit includes

First switch selectively connects the first choice terminal with the one party in the public terminal and ground terminal It connects；And

Second switch selectively connects the second selection terminal with the one party in the public terminal and ground terminal It connects,

13. high-frequency front-end circuit described according to claim 1~any one of 12, which is characterized in that

The high-frequency front-end circuit has multiple groups, and each group has the first switch circuit as the switching circuit, described the One filter, the second filter and first impedor,

The high-frequency front-end circuit is also equipped with:

Second switch circuit, with public terminal, first choice terminal and the second selection terminal；And

4th impedor,

Wherein, the first choice terminal possessed by the second switch circuit is selectively had with the second switch circuit One party connection in the public terminal and ground terminal having,

The second selection terminal is selectively and possessed by the second switch circuit possessed by the second switch circuit One party connection in the public terminal and ground terminal,

The public terminal possessed by the first switch circuit in a group in the multiple group is opened with described second The first choice terminal connection possessed by powered-down road,

The public terminal and described second possessed by the first switch circuit in another group in the multiple group The second selection terminal connection possessed by switching circuit,

4th impedor is connected to the first choice terminal and described one possessed by the second switch circuit Node on the path of the connection of the public terminal possessed by the first switch circuit in a group and by described second Institute possessed by the first switch circuit in the second selection terminal and another described group possessed by switching circuit State the node on the path of public terminal connection.

14. a kind of communication device, has:

RF signal processing circuit handles the high-frequency signal transmitted and received using antenna element；And

According to claim 1, high-frequency front-end circuit described in~any one of 13 believed in the antenna element and the RF The high-frequency signal is transmitted between number processing circuit.